Communication between electronic devices is usually accomplished by transmission of an electrical signal through an electrical connector connected therebetween, for example, a USB electrical connector commonly used at present. The USB Implementation Forum (USB-IF) declared the USB Type-C interface of an electrical connector for USB devices in 2014. The USB Type-C interface has the advantage of supporting both positive and reverse plugging. At present, there is a trend of replacing the existing Micro USB interface on the mobile phone with the USB Type-C interface in the whole mobile phone industry, thereby making the USB Type-C interface become a standardized interface in the industry.
As shown in FIG. 1, in order to make the rigidity of the USB interface compliant to the specification published by the USB-IF, the existing USB Type-C interface 2′ is added with a protection shell 21′ outside of a connection terminal, so as to guarantee enough rigidity of the connection terminal inside the USB Type-C interface 2′ when the plug connector 3′ swings along the X direction and the Z direction. However, the addition of the protection shell 21′ increases difficulty in the design process of the mobile phone, and even makes the design requirement of mobile phone not able to be met when designing an ultrathin mobile phone.